tm_symbols: Map layer: symbols

In r-tmap/tmap: Thematic Maps

Map layer: symbols

Description

Map layer that draws symbols Supported visual variables are: fill (the fill color), col (the border color), size the symbol size, shape the symbol shape, lwd (line width), lty (line type), fill_alpha (fill color alpha transparency) and col_alpha (border color alpha transparency).

Usage

opt_tm_symbols(
  points.only = "ifany",
  icon.scale = 3,
  just = NA,
  grob.dim = c(width = 48, height = 48, render.width = 256, render.height = 256)
)

opt_tm_dots(
  points.only = "ifany",
  icon.scale = 3,
  just = NA,
  grob.dim = c(width = 48, height = 48, render.width = 256, render.height = 256)
)

opt_tm_bubbles(
  points.only = "ifany",
  icon.scale = 3,
  just = NA,
  grob.dim = c(width = 48, height = 48, render.width = 256, render.height = 256)
)

opt_tm_squares(
  points.only = "ifany",
  icon.scale = 3,
  just = NA,
  grob.dim = c(width = 48, height = 48, render.width = 256, render.height = 256)
)

tm_symbols(
  size = tm_const(),
  size.scale = tm_scale(),
  size.legend = tm_legend(),
  size.chart = tm_chart_none(),
  size.free = NA,
  fill = tm_const(),
  fill.scale = tm_scale(),
  fill.legend = tm_legend(),
  fill.chart = tm_chart_none(),
  fill.free = NA,
  col = tm_const(),
  col.scale = tm_scale(),
  col.legend = tm_legend(),
  col.chart = tm_chart_none(),
  col.free = NA,
  shape = tm_const(),
  shape.scale = tm_scale(),
  shape.legend = tm_legend(),
  shape.chart = tm_chart_none(),
  shape.free = NA,
  lwd = tm_const(),
  lwd.scale = tm_scale(),
  lwd.legend = tm_legend(),
  lwd.chart = tm_chart_none(),
  lwd.free = NA,
  lty = tm_const(),
  lty.scale = tm_scale(),
  lty.legend = tm_legend(),
  lty.chart = tm_chart_none(),
  lty.free = NA,
  fill_alpha = tm_const(),
  fill_alpha.scale = tm_scale(),
  fill_alpha.legend = tm_legend(),
  fill_alpha.chart = tm_chart_none(),
  fill_alpha.free = NA,
  col_alpha = tm_const(),
  col_alpha.scale = tm_scale(),
  col_alpha.legend = tm_legend(),
  col_alpha.chart = tm_chart_none(),
  col_alpha.free = NA,
  plot.order = tm_plot_order("size"),
  zindex = NA,
  group = NA,
  group.control = "check",
  popup.vars = NA,
  popup.format = list(),
  hover = "",
  id = "",
  options = opt_tm_symbols(),
  ...
)

tm_dots(
  fill = tm_const(),
  fill.scale = tm_scale(),
  fill.legend = tm_legend(),
  fill.free = NA,
  size = tm_const(),
  size.scale = tm_scale(),
  size.legend = tm_legend(),
  size.free = NA,
  lwd = tm_const(),
  lwd.scale = tm_scale(),
  lwd.legend = tm_legend(),
  lwd.free = NA,
  lty = tm_const(),
  lty.scale = tm_scale(),
  lty.legend = tm_legend(),
  lty.free = NA,
  fill_alpha = tm_const(),
  fill_alpha.scale = tm_scale(),
  fill_alpha.legend = tm_legend(),
  fill_alpha.free = NA,
  plot.order = tm_plot_order("size"),
  zindex = NA,
  group = NA,
  group.control = "check",
  options = opt_tm_dots(),
  ...
)

tm_bubbles(
  size = tm_const(),
  size.scale = tm_scale(),
  size.legend = tm_legend(),
  size.free = NA,
  fill = tm_const(),
  fill.scale = tm_scale(),
  fill.legend = tm_legend(),
  fill.free = NA,
  col = tm_const(),
  col.scale = tm_scale(),
  col.legend = tm_legend(),
  col.free = NA,
  lwd = tm_const(),
  lwd.scale = tm_scale(),
  lwd.legend = tm_legend(),
  lwd.free = NA,
  lty = tm_const(),
  lty.scale = tm_scale(),
  lty.legend = tm_legend(),
  lty.free = NA,
  fill_alpha = tm_const(),
  fill_alpha.scale = tm_scale(),
  fill_alpha.legend = tm_legend(),
  fill_alpha.free = NA,
  col_alpha = tm_const(),
  col_alpha.scale = tm_scale(),
  col_alpha.legend = tm_legend(),
  col_alpha.free = NA,
  plot.order = tm_plot_order("size"),
  zindex = NA,
  group = NA,
  group.control = "check",
  options = opt_tm_bubbles(),
  ...
)

tm_squares(
  size = tm_const(),
  size.scale = tm_scale(),
  size.legend = tm_legend(),
  size.free = NA,
  fill = tm_const(),
  fill.scale = tm_scale(),
  fill.legend = tm_legend(),
  fill.free = NA,
  col = tm_const(),
  col.scale = tm_scale(),
  col.legend = tm_legend(),
  col.free = NA,
  lwd = tm_const(),
  lwd.scale = tm_scale(),
  lwd.legend = tm_legend(),
  lwd.free = NA,
  lty = tm_const(),
  lty.scale = tm_scale(),
  lty.legend = tm_legend(),
  lty.free = NA,
  fill_alpha = tm_const(),
  fill_alpha.scale = tm_scale(),
  fill_alpha.legend = tm_legend(),
  fill_alpha.free = NA,
  col_alpha = tm_const(),
  col_alpha.scale = tm_scale(),
  col_alpha.legend = tm_legend(),
  col_alpha.free = NA,
  plot.order = tm_plot_order("size"),
  zindex = NA,
  group = NA,
  group.control = "check",
  options = opt_tm_squares(),
  ...
)

Arguments

points.only	should only point geometries of the shape object (defined in tm_shape()) be plotted? By default "ifany", which means TRUE in case a geometry collection is specified.
icon.scale	scaling number that determines how large the icons (or grobs) are in plot mode in comparison to proportional symbols (such as bubbles). For view mode, use the argument grob.dim
just	justification of the text relative to the point coordinates. Either one of the following values: "left" , "right", "center", "bottom", and "top", or a vector of two values where first value specifies horizontal and the second value vertical justification. Besides the mentioned values, also numeric values between 0 and 1 can be used. 0 means left justification for the first value and bottom justification for the second value. Note that in view mode, only one value is used.
grob.dim	vector of four values that determine how grob objects (see details) are shown in view mode. The first and second value are the width and height of the displayed icon. The third and fourth value are the width and height of the rendered png image that is used for the icon. Generally, the third and fourth value should be large enough to render a ggplot2 graphic successfully. Only needed for the view mode.
size, size.scale, size.legend, size.chart, size.free	Visual variable that determines the size. See details.
fill, fill.scale, fill.legend, fill.chart, fill.free	Visual variable that determines the fill color. See details.
col, col.scale, col.legend, col.chart, col.free	Visual variable that determines the col color. See details.
shape, shape.scale, shape.legend, shape.chart, shape.free	Visual variable that determines the shape. See details.
lwd, lwd.scale, lwd.legend, lwd.chart, lwd.free	Visual variable that determines the line width. See details.
lty, lty.scale, lty.legend, lty.chart, lty.free	Visual variable that determines the line type. See details.
fill_alpha, fill_alpha.scale, fill_alpha.legend, fill_alpha.chart, fill_alpha.free	Visual variable that determines the fill color alpha transparency See details.
col_alpha, col_alpha.scale, col_alpha.legend, col_alpha.chart, col_alpha.free	Visual variable that determines the border color alpha transparency. See details.
plot.order	Specification in which order the spatial features are drawn. See tm_plot_order() for details.
zindex	Map layers are drawn on top of each other. The zindex numbers (one for each map layer) determines the stacking order. By default the map layers are drawn in the order they are called.
group	Name of the group to which this layer belongs. This is only relevant in view mode, where layer groups can be switched (see group.control)
group.control	In view mode, the group control determines how layer groups can be switched on and off. Options: "radio" for radio buttons (meaning only one group can be shown), "check" for check boxes (so multiple groups can be shown), and "none" for no control (the group cannot be (de)selected).
popup.vars	names of data variables that are shown in the popups in "view" mode. Set popup.vars to TRUE to show all variables in the shape object. Set popup.vars to FALSE to disable popups. Set popup.vars to a character vector of variable names to those those variables in the popups. The default (NA) depends on whether visual variables (e.g.col) are used. If so, only those are shown. If not all variables in the shape object are shown.
popup.format	list of formatting options for the popup values. See the argument legend.format for options. Only applicable for numeric data variables. If one list of formatting options is provided, it is applied to all numeric variables of popup.vars. Also, a (named) list of lists can be provided. In that case, each list of formatting options is applied to the named variable.
hover	name of the data variable that specifies the hover labels
id	name of the data variable that specifies the indices of the spatial features. Only used for "view" mode.
options	options passed on to the corresponding ⁠opt_<layer_function>⁠ function
...	to catch deprecated arguments from version < 4.0

Details

The visual variable arguments (e.g. col) can be specified with either a data variable name (e.g., a spatial vector attribute or a raster layer of the object specified in tm_shape()), or with a visual value (for col, a color is expected). Multiple values can be specified: in that case facets are created. These facets can be combined with other faceting data variables, specified with tm_facets().

• The ⁠*.scale⁠ arguments determine the used scale to map the data values to visual variable values. These can be specified with one of the available ⁠tm_scale_*()⁠ functions. The default is specified by the tmap option (tm_options()) scales.var.

• The ⁠*.legend⁠ arguments determine the used legend, specified with tm_legend(). The default legend and its settings are determined by the tmap options (tm_options()) legend. .

• The ⁠*.chart⁠ arguments specify additional charts, specified with tm_chart_, e.g. tm_chart_histogram()

• The ⁠*.free⁠ arguments determine whether scales are applied freely across facets, or shared. A logical value is required. They can also be specified with a vector of three logical values; these determine whether scales are applied freely per facet dimension. This is only useful when facets are applied (see tm_facets()). There are maximally three facet dimensions: rows, columns, and pages. This only applies for a facet grid (tm_facets_grid()). For instance, col.free = c(TRUE, FALSE, FALSE) means that for the visual variable col, each row of facets will have its own scale, and therefore its own legend. For facet wraps and stacks (tm_facets_wrap() and tm_facets_stack()) there is only one facet dimension, so the ⁠*.free⁠ argument requires only one logical value.

A symbol shape specification is one of the following three options.

1. A numeric value that specifies the plotting character of the symbol. See parameter pch of points and the last example to create a plot with all options. Note that this is not supported for the "view" mode.

2. A grob object, which can be a ggplot2 plot object created with ggplotGrob. To specify multiple shapes, a list of grob objects is required. See example of a proportional symbol map with ggplot2 plots.

3. An icon specification, which can be created with tmap_icons.

To specify multiple shapes (needed for the shapes argument), a vector or list of these shape specification is required. The shape specification options can also be mixed. For the shapes argument, it is possible to use a named vector or list, where the names correspond to the value of the variable specified by the shape argument. For small multiples, a list of these shape specification(s) should be provided.

Examples

metroAfrica = sf::st_intersection(metro, World[World$continent == "Africa", ])
Africa = World[World$continent == "Africa", ]

tm_shape(land) +
	tm_raster("cover_cls", 
			  col.scale = tm_scale(
			  	values = cols4all::c4a("brewer.pastel1")[c(3,7,7,2,6,1,2,2)]
			  ),
			  col.legend = tm_legend_hide()) +
	tm_shape(rivers) +
	tm_lines(lwd = "strokelwd", lwd.scale = tm_scale_asis(values.scale = .3),
			 col = cols4all::c4a("brewer.pastel1")[2]) +
	tm_shape(Africa, is.main = TRUE) + 
	tm_borders() +
	tm_shape(metroAfrica) +
	tm_symbols(fill = "red", shape = "pop2020", size = "pop2020", 
			   size.scale = tm_scale_intervals(
			   	   breaks = c(1, 2, 5, 10, 15, 20, 25) * 1e6,
			   	   values.range = c(0.2,2)
			   	),
			   size.legend = tm_legend("Population in 2020"),
			   shape.scale = tm_scale_intervals(
			   	   breaks = c(1, 2, 5, 10, 15, 20, 25) * 1e6,
			   	   values = c(21, 23, 22, 21, 23, 22)
			   	),
			   shape.legend = tm_legend_combine("size")) +
	tm_labels("name", options = opt_tm_labels(remove.overlap = FALSE))

## to do: replace this example:

## Not run: 
	if (require(rnaturalearth)) {
		
		airports <- ne_download(scale=10, type="airports", returnclass = "sf")
		airplane <- tmap_icons(system.file("img/airplane.png", package = "tmap"))
		
		
		
		current.mode <- tmap_mode("view")
		
		tm_shape(NLD_prov, crs = 4326) + tm_polygons() + 
		tm_shape(airports) +
			tm_symbols(shape=airplane, size="natlscale",
					   legend.size.show = FALSE, scale=1, border.col = NULL, id="name", popup.vars = TRUE)
			#tm_view(set.view = c(lon = 15, lat = 48, zoom = 4))
		tmap_mode(current.mode)
	}

## End(Not run)

########################
## plot symbol shapes
########################

# create grid of 25 points in the Atlantic
library(sf)
atlantic_grid = cbind(expand.grid(x = -51:-47, y = 20:24), id = seq_len(25))
x = st_as_sf(atlantic_grid, coords = c("x", "y"), crs = 4326)

tm_shape(x, bbox = tmaptools::bb(x, ext = 1.2)) +
	tm_symbols(shape = "id",
			   size = 2,
			   lwd = 2,
			   fill = "orange",
			   col = "black",
			   shape.scale = tm_scale_asis()) +
	tm_text("id", ymod = -2)

# also supported in view mode :-)

r-tmap/tmap documentation built on June 23, 2024, 9:58 a.m.